A bacterial culture was isolated from oil-contaminated soil based on its ability to metabolize the quinoline as the sole source of nitrogen. In this research Bacillus licheniformis strain was identified based on the result of 16S rRNA analysis. Optimized conditions were obtained with full factorial experimental design method using design expert software at temperature: 32oC, agitation speed: 200rpm, quinoline concentration: 400 ppm.The efficiency of Bacillus licheniformis for biodegradation of quinoline at the optimum conditions was determined to be 35%. Two-phase cultivation media were used with 5, 10, 15 and 20% heavy crude oil concentration in aqueous media. Resting cells of Bacillus licheniformis was shown to be capable of removing about 25% of total nitrogen in 5% heavy crude oil. GC analysis showed a decreasing trend in the activity of this strain against crude oil concentration.